3-D motion pictures are generally made by simultaneously photographing a subject using two motion picture cameras positioned to provide left and right eye views of the subject. To present the motion picture, the images recorded by the cameras are simultaneously projected onto a screen from two projectors and are optically coded in some way so that the left eye of a viewer sees only the images that were recorded by the "left eye" camera while the viewer's right eye sees only the "right eye" images. The viewer then perceives a stereoscopic or 3-D effect.
Coding of the images may be effected by the use of what are in effect shuttered spectacles worn by a viewer. The shutters effectively block and unblock the view from each eye alternately in timed relation to projection of the images onto the screen so that the viewer's right eye is blocked when left eye images appear and vice versa. This technique is referred to as "alternate eye" 3-D and is discussed, for example, in U.S. Pat. No. 4,424,529 (Roese et al.). Another technique involves the use of oppositely polarized filters on the projection lenses for the respective images and correspondingly polarized filters in glasses worn by a viewer.
Spectacular 3-D motion pictures can be made using large format films such as those that are available from Imax Systems Corporation of Toronto, Canada under the registered trade marks IMAX and OMNIMAX. The use of large format films has become possible as a result of development of the so-called "rolling loop" film transport mechanism for cameras and projectors. U.S. Pat. No. 3,494,524 to Jones discloses the principle of a rolling loop transport mechanism. A number of improvements in the original Jones mechanism are disclosed in U.S. Pat. Nos. 3,600,073, 4,365,877 and 4,441,796 (Shaw). All of these patents have been assigned to Imax Systems Corporation.